1. Field of the Invention
The present invention relates to a slot machine having special symbols and a control method thereof.
2. Discussion of the Background
In conventional slot machines, when a player inserts game media such as medals, coins or bills into an insertion slot of the slot machine and presses a spin button, then a plurality of symbols are scroll-displayed to a display portion provided on the front surface of a casing and, thereafter, the respective symbols are automatically stopped, as disclosed in U.S. Pat. Nos. 6,960,133, 6,012,983 and 6,093,102. In this case, when scroll-display of respective symbols starts by an input from the spin button, symbols are selected using random numbers, and the selected symbols are stop-displayed to the display portion. Then, when a combination of the stop-displayed symbols along a winning line is a predetermined winning combination (prize), a payout is conducted.
Further, among conventional slot machines, there are some slot machines which conduct two types of payouts which are a payout determined according to the combinations of symbols rearranged along winning lines and a payout determined according to the number of displayed scatter symbols, as disclosed in U.S. Pat. No. 6,604,999 and US 2002-0065124-A1. In such a slot machine which conducts a payouts based on such scatter symbols, there is no relationship between payouts and positions at which the scatter symbols are displayed.
In such conventional slot machines, symbols to be stop-displayed (rearranged) typically have a predetermined picture (e.g. watermelon, cherry, number “7”, etc.). However, since only similar symbols are used in a large number of slot machines, there have been cases where a player is unlikely to feel freshness. This has caused a problem of making the player soon bored of a game.
In light of the aforementioned problem, the present invention has been devised, and an object of the present invention is to provide a slot machine having special symbols that have a player feel freshness.
The contents of U.S. Pat. No. 6,960,133, U.S. Pat. No. 6,012,983, U.S. Pat. No. 6,093,102, U.S. Pat. No. 6,604,999 and U.S. 2002-0065124-A1 are incorporated herein by reference in their entirety.